Lighting fixture backplate



FIG. 1 is a side elelvational view of the lighting fixture backplate in accordance with my design, illustrated in an environment of a lamp;

FIG. 2 is a top plan view of the lighting fixture backplate in accordance with my design, the bottom being identical thereto;

FIG. 3 is a front side elevational view of the lighting fixture backplate in accordance with my design;

FIG. 4 is a left side elevational view of the lighting fixture backplate in accordance with my design, the right side being a mirror image thereof; and,

FIG. 5 is a rear side elevational view of the lighting fixture backplate in accordance with my design.

The broken lines show the environment in which the article is used and are not considered part of the design claimed. 

The ornamental design for the lighting fixture backplate, as shown and described. 